Combined projectile and gas-check



(No Model.) A. BALL.

COMBINED PROJEGTILE AND GAS GHEGK. No. 4051390.

Patented June 25 ATTBRNEY- UNITED STATES PATENT ()EEICE.

ALBERT BALL, OF CLAREMONT, NEIV HAMPSHIRE.

COMBINED PROJECTILE AND GAS-CHECK.

SPECIFICATION forming part of Letters Patent No. 405,690, dated June 25,1889.

Application filed February 21, 1887. Renewed May 3, 1889. Serial No.309,546. (No model.)

To aZZ whom it may concern/.-

Be it known that I, ALBERT BALL, a citizen of the United States,residing at Claremont, in the county of Sullivan and State of NewHampshire, have invented certain new and useful Improvements in aCombined Projectile and Gas-Check or Sabot; and I do hereby declare thefollowing to be a full, clear, and exact description of the invention,such as will enable others skilled in the art to which it appertains tomake and use the same.

The object of my invention is to combine with a bullet or projectilemade of hard metal-such as iron, steel, &c.a gas-check or sabot thatwill not be upset by the action of the explosive, and that will notinjure the riflin g of the barrel of the gun, and also to so connect theprojectile and the sabot that when the latter is forced into the groovesof the rifle by the explosive it will impart rotation to the projectileand yet readily separate from it upon leaving the gun. These objects areimportant, and means heretofore used have failed to accomplish them withsufficient certainty of action and simplicity of construction.

I make the sabot or gas-check, preferably, of soft metalsuch as lead,tin, or alloys of lead and tin, &c.tl1at can be easily melted in a ladleand run into molds of proper shape. The metal, however, may be swagedinto the form desired. The gas-check may also be made by swaging ormolding paper, papiermach, vulcanized fiber, leatheroid, or leather, orit may be made from asbestus, jute, flax, or cotton, these substancesbeing treated or mixed with paste, shellac, starch, or gum compounds, orcompounds of tallow, paraffine, barberry-tallow, or beeswax, and thenpressed into the proper form.

Figs. 1, 2, 3, 5, and 7 represent side views of the projectiles orbullets, the gas-checks and outside wrapping being shown in section.Figs. 4: and 6 represent longitudinal sections of both gas-check andbullet.

The sabot in each figure is indicated by 1, the projectile by 2, and theexterior envelope or wrapper by 3, and a indicates a substanceinterposed between the sabot and the projectile to prevent theiradhesion. The body of the sabot is made with a depression in one end toreceive a correspondinglyshaped end of the projectile. These have equaldiameters, and the wrapper that surrounds them both is a right cylinderand closely embraces the surface both of the projectile and the sabot.This wrapper is made of linen or cotton cloth, of paper, or of tin orlead foil or other equivalent material, which is rolled or wound tightlyaround the projectile and sabot after they have been placed in properrelative position. The end of the wrapper extending beyond the base ofthe sabot is twisted or pinched together and may be cemented orsoldered, if thought desirable.

In some cases I provide a recess in the end of the sabot -or gas-checkand press the folded or twisted end of the wrapper into it. This recessgives greater lateral effect to the explosive, whereby the material ofthe sabot is forced into the grooves of the rifle more thoroughly.

The wrapper extends over the whole length of the gas-check and acrossone of its ends, and also over a large part of the projectile. Itprevents the hard metal of the projectile from wearing the riflin g ofthe gun-barrel and holds the sabot and projectile together securely forhandling or transportation, and in operation, when the soft material ofthe gascheck has been forced into the grooves of the gun by theexplosion, it tends to impart the rotary motion of the same to theprojectile. An efficient means for producing this latter effect isprovided in the extended contact between the parts. Heretofore sabotshave been combined with projectiles so as to leave an air-chamberbetween them, or between one of them and the covering or wrapper. It ischaracteristic of my improvement that it leaves no air chambers orspaces about or at the base of the projectile; but this is placed infull contact with the sabot over an area as large at least as across-section, there being interposed only a thin layer of somesubstance such as soapstone, plumbago, or a mixture or compounds ofthese, or a layer .of paper or similar material-to prevent adhesion. Thesabot, therefore, bears practically upon the whole base of theprojectile at the very beginning of any movement caused by the explosionand communicates motion to the projectile at once. In constructionsheretofore ICO made wherein the sabot did not fit the projectile therewas in operation an interval during which the sabot was independentlymoved forward and the air expelled from intermediate spaces, and duringwhich the force of the explosion did not fully reach the projectile. v

The simultaneous forward and rotary movement of the sabot and theprojectile is further insured by my construction. (Indicated in Figs. 1and 2.) As there shown, the projectile is provided with an extensionwhich is angular in cross-section, and it fits a 'similar-shaped recessin the sabot, whereby independent rotation, so long as the parts areheld in contact, is prevented. An equivalent is shown in Fig. 5, whereinthe extension is represented as made with a corrugated surface, andvarious other equivalent forms will readily suggest themselves.

The pointed form of the projectile has the further effect to force thematerial of the gascheck to move laterally and into the grooves of therifle as soon as the gun is fired and while the inertia of theprojectile is at first being overcome. It is obvious that the height ofthe cones or pyramids on the base of the projectiles may be variedwithout materially affecting the operation. They should probably not bemade so high, however, as to pierce through the sabot, or the lattershould be made sufficiently long to leave a body equal in diameter tothe projectile, for the reason that a ring of soft material is moreliable to be upset or otherwise displaced by the eifect of. theexplosion, and the best result is secured by having the entire space ofthe barrel of the gun from. the point of the bullet to the baseof thegas-check filled as solidly as practicable, and by giving to the lattera sufficient body to prevent its moving unequally or irregularly, as isthe case where light rings or plates are used, and especially when theyare so placed as to leave chambers or air-spaces between them and thebullet or between either of them and the covering. I also prefer to makethe sabot of the relative length indicated, or about as long on itsexterior as the diameter of the bore of the gun, whereby upsetting orany backward or irregular movement of the surface of the soft metal isobviated.

From the above description it will be seen that the covering, whichtightly embraces all the sabot and a large part of the projectile, andthe extended bearing provided between the two latter, which is in nocase less than the area of a cross-section of the bullet, com- .bineswith its pyramidal or corrugated base to hold the parts together.

The explosion crowds the material of the sabot into the rifled groovesand also the wrapper, which serves as a part of the gascheck, but onlyincidentally, since the grooves would befilled and the windage obviatedwere no covering employed. It may also be noted that the frictionbetween the gas-check and the bullet would be sufficient to impart therotary motion of the former to the latter without the covering, sincethe bearing between the two extends transversely through the'whole areaof a cross-section of the bore. The lateral ex pansion of the softmaterial of the sabot into the grooves partially disrupts the covering,and as the projectile has little or no friction to overcome in thebarrel and no resistance except that due to the air'in said barrel itsvelocity will be sufficient the instant it escapes from the gun to severits connection with the sabot, which will be retarded by friction in thegrooves, the separation of the parts being aided by the materialinterposed to prevent adhesion.

Sabots of compound form, embracing an exterior ring and an interiorly orcentrally located cup, plug, or other piece, have been applied toprojectiles, and I do not, broadly, claim a sabot having a lateralextent equal to that of the projectile and in contact with the same.

In another combination a projectile has been provided with exteriorspiral grooves on its forward portion and also on its rear portion,which latter was embraced by a sabot having similar interior grooves.The proj ectile was also provided with a central longitudinal openingand a device located therein adapted to cause the rotation of theprojectile by the resistance of air. Provision was also made in thesabot for sufficient windage to cause rotation of the projectile byimpact upon the walls of the posterior grooves of the same before itleft the barrel.

In my sabot and projectile there are no spiral grooves or lines, nor anymodification of form to produce rotation either before or afterleaving'the barrel, the grooves of the barrel alone being relied uponfor this effect.

My construction, though resembling in a general manner as to its mainfeatures devices heretofore described, is more economical and efficientthan any known to me. It is homogeneous in its composition and simple(not compound) in its structure, and is less liable to be disrupted inthe barrel than those which are composed of an exterior ring having anexterior cup or plug or those having deep exterior and interior groovesand made smaller than the projectile to provide sufficient windage torevolve it in the barrel.

Heretofore a rubber sabot having a diameter equal to that of theprojectile and closely fitting its base without an interposed film hasbeen described, and also a complex sabot en tirely inclosed in a clothcovering. In use this last-described sabot was separated from theprojectile by pins or wedge-shaped pieces.

In neither construction was there a covering common to the two parts.Such combinations I do not claim, nor do I claim covering both a sabotand projectile having uniform diameter, and thereby holding them incontact; but my claim is limited to the particular combinations pointedout.

Having thus described my invention, what I I desire to claim and secureby Letters Patent 1. A projectile having a pyramidal base provided Witha sabot of homogeneous composition and simple structure applied closelyto the Whole area of its base, and secured to it by a temporary fibrouscovering that closely fits both the sabot and the projectile,substantially as specified, whereby motion in a forward direction willbe simultaneously imparted to them by the explosion.

2. A projectile having a pyramidal base provided with a sabot ofhomogeneous composition and simple structure applied closely to thewhole area of its base, and secured to it by a temporary fibrouscovering that closely fits the sides of them both, and is secured at therear of the sabotin a recess formed therein, substantially as set forth.

3. A projectile having a sabot of homogeneous composition and simplestructure applied to the Whole area of its base, a film to preventadhesion interposed between the sabot and projectile and normally incontact with the geneous composition and simple structure fitting theWhole area of the base, and a covering tightly embracing both With aninterposed film to prevent adhesion, substantially as set forth, wherebythe main body of the projectile is adapted to be rotated with the sabotin a gun-barrel and separated from it as soon as it leaves the barrel.

In testimony whereof I affix my signature in presence of two Witnesses.

ALBERT BALL.

Witnesses:

FRANK A. BALL, 0. BELLE DUTION.

